Animals of Migration

The wildebeest

Their scientific name is Connochaetes taurinus. Their average height is 45-57 inches. The average with for a female is 300 to 575 pounds and 360 to 640 pounds for a male Wildbeest.

Wildebeest thrive in the grasslands of the Serengeti-Mara. They are common in protected grassland and woodland areas across East Africa.

The wildebeest may not be the star attractions of East Africa's wildebeest migration (top billing is reserved for the lions), but they are without doubt the spectacle's essential element. Their quest for short, new growth grasses on the plains of Tanzania and Kenya leads them on an endless 300 mile circuit of the savanna. In fact, much of what we understand today about the ecology of the Serengeti-Mara region is the result of complex interactions among the wildebeest, the grasses and plant life, the geography, and the wildebeest's predators.

Wildebeest are born to run. A foal can stand on its feet minutes after birth, and can trot steadily beside its mother just a couple of hours later. Wildebeest are also born to assemble; most East African wildebeest are born in a short two to three week period in February. The flood of newborns is a clever, if grim, defense against predators; plenty of foals will be lost to the lions and hyenas. Plenty more will survive to join the migration.

Male wildebeest can reach nearly five feet at the shoulder and can weigh more than 600 pounds. Females are sexually mature at 16 months, but first breeding is commonly at 28 months or so. Males first breed at four or five years, when they've become strong enough to defend territory during rutting season (March-April). Fortunate wildebeest can live as long as 20 years.

Although a million plus wildebeest take part in the migration, actual wildebeest herds are much smaller. When the migrants reach good forage, the migratory columns disperse into smaller groups of cows and foals and groups of young bachelor males. The columns reform as the grasses dry and the quest for young green shoots continues.

The wildebeest's preferred forage is the short grass that grows in the alkaline rich soils of the southern Serengeti. Unfortunately for the wildebeest, those grasses are only available for a brief time each year - just a couple of months following the short rains of November and December.

The relationship between herbivore and forage is complex. Consumption of the mineral and protein-rich short grasses fattens cows who give birth on the short grass plains, and consumption of the short grass strengthens all members of the herd for the long migration ahead. The grasses benefit, too. Herbivore manure, of course, fertilizes the soil. Herbivore hoofsteps, gallops, stamps and scratches till and aerate. Herbivore teeth clip the grassy leaves, which encourages new growth, and, in a another complex interchange, prompts the grasses to produce leaves and stems with denser concentrations of nutrients. It is as if the grasses are rewarding the wildebeest for clipping them short.

The wildebeest have also affected the balance of predators in the region. The numbers of lions and hyenas have increased as a result of the steady availability of prey. For the lions, strict territoriality limits their ability to pursue the herds as they move from pasture to pasture. The hyena social system allows for more mobility. In any case, more lions and hyenas makes life difficult for competing predators such as leopards and cheetahs. An adult wildebeest would not be on the menu for either of these big cats (although a calf might do), but neither is well-equipped to defend itself, its kills or its young from lions and hyenas. What's good for lions and hyenas turns out to be bad for leopards and cheetahs

More important to the success of the lions than the access to prey has been the resurgence of wooded areas in the ecosystem. Acacia stands provide cover for hunting lions and protection for their young. Researchers attribute the increasing density of trees to wildebeest activity. Just as with the short grasses, manure and hooves prepare the soil for seedlings. By closely cropping the tall grasses, the wildebeest allow more sunlight to reach those seedlings. The close cropping serves as a kind of fire suppression system, too. Fires that do manage to flare across the dry, brown landscape have less fuel to consume and burn cooler, allowing more acacia seedlings to reach adulthood.

Just as the short grasses reward the wildebeest who feed on them with denser nutrition, the wildebeest reward the beasts who prey upon them with safer places to live. From bottom to top, the story of the Serengeti-Mara ecosystem is the story of the wildebeest.